BDBag release 1.5.3

Release Notes

Compatibility and feature micro release.

• Added a monkeypatch for hashlib.algorithms_guaranteed prior to the
  import of any bagit code so that bagit-1.7.0 (which assumes
  algorithms_guaranteed is present, but in reality only consistently
  exists on Python 2.7.9 or greater) can still be used by bdbag on
  systems that only have Python 2.7.0 to 2.7.8 installed.
  Lifted the strict pin on Python>=2.7.9. Note that this won't make
  standalone bagit installations work on these systems, but it will
  allow bdbag to successfully import and use bagit as a library.
  Additional notes
  here.

• Added code to properly url encode whitespace and other illegal
  characters in the filename field of fetch.txt, per the bagit spec.
  This will automatically be encoded when bdbag generates a bag from a
  remote-file-manifest, and will automatically decoded when attempting
  to resolve files via fetch. Added a corresponding unit test.

• Added a new CLI validate option: --completeness. This is in parity
  with bagit CLI options and is useful primarily for determining which
  files in fetch.txt have not yet been retrieved. Added a corresponding
  unit test.

• Added code in the CLIs to print stack traces in when --debug is
  specified.